Gastrinomas are the most common symptomatic, malignant pancreatic neuroendocrine tumor (pNET) in patients with or without MEN1 and sufficient numbers of these patients have been entered into our protocols to allow systematic assessment. Studies are now underway, evaluating the natural history of these tumors including the definition of factors determining prognosis and cause of death. Our studies have identified a cohort of 25% of patients in whom the gastrinomas have aggressive growth and 25% who have multiple endocrine neoplasia type 1 (MEN1). During this year information from our prospective studies was used to write four guideline and position papers dealing with the diagnosis of these tumors, treatment of advanced disease and pharmacological approach to management. Also two colloborative studies with Prof T Ito, Kyushu University were done. . One examining the epidemiology of pancreatic and GI neuroendocrine tumors in Japan with recent trends and a second the protential usefulness of serum Chromogranin A assays in Japan to identify patients with neuroendocrine tumors. Furthermore, chapters in both Goldman's and Harrison's textbooks of medicine as well as Yamada's and Sleisnger/Fordtran's Textbooks of Gastroentology were published or are in press.